Internet Engineering Task Force (IETF) P. Saint-Andre
Request for Comments: 7712 &yet
Category: Standards Track M. Miller
ISSN: 2070-1721 Cisco Systems, Inc.
P. Hancke
&yet
November 2015
Domain Name Associations (DNA)
in the Extensible Messaging and Presence Protocol (XMPP)
Abstract
This document improves the security of the Extensible Messaging and
Presence Protocol (XMPP) in two ways. First, it specifies how to
establish a strong association between a domain name and an XML
stream, using the concept of "prooftypes". Second, it describes how
to securely delegate a service domain name (e.g., example.com) to a
target server hostname (e.g., hosting.example.net); this is
especially important in multi-tenanted environments where the same
target server hosts a large number of domains.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7712.
Saint-Andre, et al. Standards Track [Page 1]RFC 7712 XMPP DNA November 2015Copyright Notice
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Table of Contents
1. Introduction ....................................................3
2. Terminology .....................................................4
3. Client-to-Server (C2S) DNA ......................................4
3.1. C2S Flow ...................................................4
3.2. C2S Description ............................................5
4. Server-to-Server (S2S) DNA ......................................5
4.1. S2S Flow ...................................................6
4.2. A Simple S2S Scenario .....................................10
4.3. No Mutual PKIX Authentication .............................12
4.4. Piggybacking ..............................................13
4.4.1. Assertion ..........................................13
4.4.2. Supposition ........................................15
5. Alternative Prooftypes .........................................16
5.1. DANE ......................................................16
5.2. POSH ......................................................17
6. Secure Delegation and Multi-Tenancy ............................18
7. Prooftype Model ................................................18
8. Guidance for Server Operators ..................................19
9. IANA Considerations ............................................20
9.1. POSH Service Name for xmpp-client Service .................20
9.2. POSH Service Name for xmpp-server Service .................20
10. Security Considerations .......................................20
11. References ....................................................21
11.1. Normative References .....................................21
11.2. Informative References ...................................23
Acknowledgements ..................................................24
Authors' Addresses ................................................24
Saint-Andre, et al. Standards Track [Page 2]RFC 7712 XMPP DNA November 2015
1. Introduction
In systems that use the Extensible Messaging and Presence Protocol
(XMPP) [RFC6120], it is important to establish a strong association
between the DNS domain name of an XMPP service (e.g., example.com)
and the XML stream that a client or peer server initiates with that